Amphibious Assault Ships support US Marine Corps expeditionary forces for extended periods of time. They in some ways resemble small aircraft carriers and are capable of supporting both Marine air and rotorcraft and a variety of amphibious vehicles. The landing helicopter deck (LHD) class of multipurpose amphibious assault ship was designed to facilitate the use of the AV-8B Harrier, Landing Craft Air Cushion (LCAC) hovercraft, and the full range of Navy and Marine Corps helicopters, landing craft and amphibious assault vehicles. The landing helicopter assault replacement (LHA®) amphibious assault ship meets future Navy-Marine Corps requirements and is able to support the expanded capability of 21st century expeditionary strike platforms such as the Marine variant of the V-22 Osprey helicopter and the F-35B Joint Strike Fighter airplane. The F-35B is capable of short runway take-off and vertical landing (STOVL).
The flight decks of the LHD and LHA class ships that accommodate a variety of air craft have nine landing spots; six port and three starboard. Legacy helicopter and AV-8B flight operations have been conducted effectively for many years from these ships. However, the introduction of the MV-22 has to these amphibious assault ships has resulted in flight deck warping during flight operations. During MV-22 ship integration tests aboard the USS Iwo Jima (LHD 7) in June 2004, there were reports of excessive heating and large deflections of the flight deck in the vicinity of the aircraft's right nacelle. The USS Bataan (LHD 5) also reported similar events in which excessive heating and large deflections of the flight deck were observed during V-22 ship integration tests in July 2005. The deflections were reported to occur while the aircraft was sitting on the deck turning rotors and began to appear after approximately 10 minutes of aircraft operation. Once the engines were turned off, or the aircraft launched, it appeared to take several hours for the deck to return to its “original” shape. Other items of concern noted from these reports include the discoloring of the flight deck non-skid coating, discoloring of the paint and primer on the underside of the deck plate, and charring of the overhead insulation. Subsequent Navy assessments of the thermal loads imposed by the landing of the F-35B Joint Strike Fighter on these ships indicated unacceptably severe heating of the deck and its (organic base) nonskid coating during landing.
The hot engine exhaust of both MV-22 Osprey and the F-35B is directed onto the horizontal deck surface, thereby subjecting the deck plate surface to higher than normal temperatures. Because the localized region of heating (and plate expansion) is surrounded by unheated deck plate and is welded to a deck support structure (longitudinal and transverse stiffening beams), the mechanically constrained thermal expansion is accommodated by deck plate buckling. This buckling occurs at a critical buckling stress established by the deck plate thickness and elastic modulus and by its support conditions. This buckling stress results in significant forces applied to the welds between the deck plate and the support structure. Initial calculations by Davis et al. (See Edward L. Davis, Young C. Hwang and David P. Kihl, “Structural Evaluation of an LHD-Class Amphibious Ship Flight Deck Subjected to Exhaust Gas Heat from a MV-22 Osprey Aircraft” NSWCCD-65-TR-2006/12 Mar. 2006) indicate that the forces are sufficient to cause local plastic deformation which is likely to result in fatigue failure of the deck before the ship reaches its design life.
In a related previous effort, the Applicant designed a passive approach for jet blast deflection during launch operations aboard aircraft carriers which demonstrated the ability to eliminate seawater-cooling systems for jet blast deflectors, reducing maintenance and maintaining the existing time period between launches. See International Application No. PCT/US2007/012268 entitled “Method and Apparatus for Jet Blast Deflection,” filed May 23, 2007, and U.S. patent application Ser. No. 12/301,916 filed Nov. 21, 2008, entitled “Method and Apparatus for Jet Blast Deflection,” of which are hereby incorporated by reference herein in their entirety.
The flight deck of the LHD(A) class of ships is 9/16″ thick and made of HY 100 steel. It is primed and then coated with an epoxy based non-skid coating that is gradually degraded during a deployment. The coating is therefore designed to be easily removed and a new coating reapplied during routine overhaul of the ship. Impingement of the high temperature MV-22 and F-35B engine plumes upon this coating is likely to result in its rapid degradation during flight operations and so a new high temperature nonskid coating is required. Atmospheric pressure thermal spray coating concepts can apply coatings directly onto the deck surface, making this a promising approach for high temperature nonskid coating material application. However, these coatings are susceptible to delamination during severe thermal cyclic loading and have low strengths.
Heretofore the prior art has failed to be able to adequately dissipate or protect the ship decks from the exhaust of high temperature plumes of jet craft.
Moreover, regarding buildings, structures and housings, the prior art has failed to be able to efficiently minimize or contain the additional energy expenditure necessary to transfer heat or cooling to intended areas of the buildings, structures, housings or areas. Existing heating and cooling systems for buildings, structures, and housing are also structurally parasitic, since they require architectural accommodation to provide the necessary space and support.